Bent’s Old Fort. which was built after the abandonment of El Pueblo, was designated a National Historic Site and National Historic Landmark in 1960. It was the headquarters of Bent, St. Vrain & Co., which grew into a vast Southwestern trading empire with stores in Taos and Santa Fe. Serving multiple functions—fort, trading post, residence, way station, supply depot and neutral site for negotiations with local Indian tribes—Bent’s Fort became a Santa Fe Trail landmark and cornerstone of the fur trade.
From 1833 to 1849, the fort was the only permanent settlement in the region not under the jurisdiction and control of Native Americans or Mexicans. As such, it played a very significant role in the presence of The United States there. Through it came U.S. Army explorers and American frontiersman, notably John C. Frémont who used the Fort as a staging and replenishment base for his expeditions and Kit Carson, who was employed as a hunter by the Bent brothers in 1841. In 1846, during the Mexican–American War, it was to be a vital staging area for Colonel Stephen Watts Kearny’s “Army of the West”.
Just as with El Pueblo, what remains of the original property is archeological. However, the impressive reconstruction is faithful to descriptions of the time. Thus, we see a structure built of adobe bricks, 180 feet long and 135 feet wide. At 15 feet in height and four feet thick, the walls of the original fort would have made it the strongest defensive construction west of Ft. Leavenworth, Kansas. On the northwest and southeast corners of the property you will see hexagonal bastions, in which, originally, cannons were placed. The walls of the fort also served as walls of rooms, all of which faced inwardly on to a court or plaza. The walls were loopholed for musketry, and the entrance was through large wooden gates of heavy timbers.
The adjective “Old” in Bent’s Old Fort, is used because William Bent built a second trading post and defensive redoubt when forced to abandon the original after a great cholera epidemic struck the Cheyenne and other Plains Indians in 1849. At first, he moved his headquarters north to Fort Saint Vrain on the South Platte before returning south in 1852 to Big Timbers, near today’s town of Lamar. In the fall of the following year, work began on a stone fort on the bluff above Big Timbers, from where he was to conduct his trading business until 1860. This new structure was to become known as Bent’s New Fort.